Man-made boards, such as fiberboard, e.g., medium density fiberboard; hardboard; chipboard; oriented strand board-fiberboard composites; particle board; oriented strand board-particle board composites; and the like, may be formed into articles having contoured portions simulating stiles, rails, panels, or other desired features of a door facing or skin. Such articles may be formed to include one or more interior depressions or raised contours simulating panels or other decorative features. Such formed depressions and contoured portions may replicate a natural wood, paneled door. Similarly, steel sheets and cross-linked polymer compositions, frequently reinforced with fiberglass, may be formed suitable for use as a molded door skin from which a door may be manufactured.
With respect to conventional doors, molded door skins may be adhesively secured to a wood frame support structure to produce a finished door. Rails and stiles forming the frame provide additional structural support for the door. Such doors are well known in the art, and provide consumers with an aesthetically appealing, yet cost efficient alternatives to traditional, solid wood doors.
It is difficult to reverse mold and to emboss deep draws into a fiberboard panel due to stretching and breaking of the fibers. A reverse molded fiberboard sheet is stretched more on its visible outer surface than on its interior surface (surface in contact with a raised mold surface) making reverse molding much more difficult when attempting to provide sharp, crisp design detail in a raised panel that simulates natural wood millwork. More recently, a reverse molded product has been engineered that allows for above-plane profiling, such as disclosed in U.S. Pat. No. 6,588,162, which is incorporated herein by reference, and the assignee of which is the assignee hereof.
There continues to be a growing demand for highly detailed above plane profiling designs, yet these products are more costly to produce. The use of existing high throughput methods for assembling doors is a necessity for minimizing manufacturing costs for above plane detailing. This necessitates using conventional hot or cold press processing where direct contact between skins and framing is a critical constraint, not easily accomplished when dealing with above plane profiling elements. In particular, conventional doors having below plane profiles are aligned one on top of another in a press. Because the detailing is below plane, the requisite contact between the planar portions of the door to the wooden frame is made. However, when pressing doors having above plane profiling, spacers are typically used to insure contact is made at the peripheral portions of the door skin to the frame. This increases the costs of processing such doors.
Another problem associated with above plane wood composite articles is in stacking a plurality of molded articles for efficient shipping. Because of the relative fragility of the above plane decorative portions, spacers are typically used so that the decorative molded portions of one article do not make excessive contact with an adjacently stacked article. The resulting stack can be quite heavy, in excess of several hundred pounds, so substantial force is applied to the door skins toward the bottom of the stack. Moreover, due to the contour, adjacent skins will typically make contract at a plurality of relatively small locations, thus causing substantial pressure to be exerted at those locations.
The present invention provides a solution to these competing interests by generating two differing but complementary profiles, one for a first side of the door or door skin and one for the opposite side of the door or door skin where each allows and fits onto the other, while still providing direct contact in the stile and rail zones of the door in order to permit use of conventional door layup practices.
In particular, the present invention is based on the recognition that both sides on surface profiles of a molded skin door do not have to be identical to the other. In particular, it is rare that both sides of a door are visible at the same time. Conventional practice reflects the history of construction materials using solid wooden stiles and rails and panel components, which generated identical appearances on both sides of typical passage doors as a default. The present invention departs from the conventional practice in the prior art, which historically yielded identical appearances on both sides.